Williams' inspiring movie the Dead Poets Society will be screened in the open air in Merrion Square tonight at 8pm.

The 1989 movie saw the comic actor move away from humour and stand-up to play an English teacher inspiring his students to seize the day.

The outdoor screening is being organised by Happenings, who organise spontaneous events in Limerick and Dublin.

The group is also showing Good Will Hunting on Saturday night in Fitzwilliam Square at 7.30pm.

It was this 1998 film, written by Matt Damon and Ben Affleck, that earned Williams an Oscar for best-supporting actor.

Both outdoor screenings are ticketed and cost from €5 to €10 but all money will go to mental health charities. Tonight's proceeds go to Pieta House and Saturday night's charity has yet to be confirmed.

"With the tragic passing of a true legend Robin Williams, we think it's time to open up the conversation on mental health," Happenings said.

The Light House cinema in Smithfield is also staging screenings and again all proceeds will go to charity. Aladdin will be shown on August 23 and Good Will Hunting is being screened on August 24. Takings are being donated to Pieta House.